Cutter spindle and feed mechanism therefor



' Nov. 10, 1953 R. J. STUART ET AL 2,658,423

CUTTER SPINDLE AND FEED MECHANISM THEREFOR Original Filed Feb. 16. 1948 2 Sheets-Sheet l INVENTORS I ATTORNEY;

Original Filed Feb. 16. 1948 1953 R. J. STUART ET AL 2,658,423

CUTTER SPINDLE AND FEED MECHANISM THEREFOR 2 Sheets-Sheet 2 INVENTORS.

iw M BY i wf ATTORNEYJ Patented Nov. 10, 1953 CUTTER SPINDLE'AND EEED MECHANISM- THEREFOR" Robert 1. Stuart, Waukegan, Ill., and Allen D. Gunderson, Racine,,Wis., assignors, to George Gorton; Machine (10., Racine, Wis., a..crp0r.a--

tion of Wisconsin Original applicationFebruary 16, 1948; Serial No.

1951, SerialNo. 227,494

2 Claims.

Qur invention relates to certain improvements. in cutter splndles and feed mechanism therefor, and: more specifically topowered feedmechanisms for progressively feeding a rotary cutter. spindle? axially toward a work pieceduring lat.- eral. movements of thespindle; over. the work piece; and the nature and objects of the invention will be readily recognized by, those skilled in-the art in light.- of the following, explanation and detailed-description, of. theaccompanying drawing illustrating. what wenow consider. to be one preferred embodiment of our invention from among various embodiments, adaptations, forms, arrangements and combinationsof which the invention is. capable within thebroad spirit and scope thereof.

This-applicationis filed asdivisionof our. copending parent. application. Serial No. 8,496, filed February 16, 1948, for Apparatus. for the Production of Integral Blade Turbine Wheels andthe Like Units.

An-object of our invention istoprovide for progressively feeding arotary cutter into a work pieceas, the cutter is laterally moved over. the work piece in lateral cutting engagement therewith.

A further objectv is. to. provide structurally simple and mechanically efficient powered mechanism for automatically progressively feeding a rotary cutter. to a predetermined'depth of cut ina workpiece.

Another object isto provide mechanism adapted to be mountedon and carried by a universally laterally movable supportingstructure mounting thereon an axially movable cutter spindle, for progressivelyv feeding the spindle toward a work pieceduring lateral movements of the'spindle.

A, further object is to provide an efficient mounting and arrangement ofapower drive for transmissionfor such a spindle feed mechanism so, mounted and associated. with the cutter spindle andits movable supportingstructure;

A further. object'is to provide apower driven cammember for feeding engagement with-a universally laterally movable cutter. spindle'to'feed the spindle axially.

A furtherobject is to provide such a cam member which may be readily removed and replaced by another, cam member havingdifferent spindle feedcharaeteristics.

Andanother object is to provide an arrangement of powered spindle. feed mechanism for feeding mechanically from a remotepower unit, acutter spindle mounted for feeding movements axially on a supportingstructure; mounted for universal lateral movements,

Divided. and this application,v May 21,.

With the, foregoing, and various other. objects, features andresults in view which willbe readily. recognized. from, the following detailed, description, and explanation, our invention consistsin certain-novel features in design and con-. struction andincombinations and sub-combinations of parts and elements, all as will be more fully referred to and specified hereinafter.

Referring. to the accompanying drawings in which similar reference characters refer to corresponding parts and. elements throughoutithe several figures thereof:

Fig. 1 is.a view in perspective of aportion of a tracer controlled, .pantographie type of engraving or milling machine embodying therein an adaptation of a cutter spindle, cutter spindle mounting and powered cutter spindle feed mechanism of our-invention.

Fig. 2 is a view in side elevation of the cutterhead, cutter spindle and powered spindle feed mechanism of" the machine of Fig. 1, the feedeam and'its mounting being shown in Ver tical section.

Fig. 3 is a view in side elevation showing the cutter spindle and spindle feed cam in their mounted-positions on the cutter head and the cutter head supporting link, respectively.

Fig. 4'is a view in top' plan showing the-mountingofthespindle feed cam and its driving worm and'shaft' on the cutter head supporting link;

Fig. 5'isa detailed view in bottom plan of'the feed cam.

An adaptation of a cutter spindle and powered cutter spindle feed of our invention for progressively feeding a-cutter spindle towardand a cutting tool thereon into a work piece as the cutting tool is'moved laterally through the work piece in cutting engagement therewith, is shown byway; offexample-as embodied in a tracer controlled, pantographic engraving machine of a particular type. The invention is not, however, limited or restricted to this particular type of machine, or for.- performing any specific character of-work, as broadly the cutter spindle-and power feed-mechanism combination and. organization exemplifiedby this example is intended and adapted for use in any machine or organization where. it may be desiredto progressively, automatically feed. a laterally movable cutting tool into a work piece during lateral cutting I movements of that tool through the work piece.

Referring to Fig. 1 of the drawings, the examplemachine happens to be of the general tracer controlled, pantographic type illustrated insuch U'. S. patents-as the following, namely, 1,790,581January 27, 1931-; 1,881,'500'October 11, 1932; 1,925,'036-August 29, 1933; and 2,000,838--May 7, 1935; in that it embodies the same general arrangement and association of a tracer controlled pantograph with a rotary cutter spindle mounted in a pivoted link supported cutter head for universal lateral movements by the movements of the pantograph in tracing a pattern to thereby universally laterally move a cutting tool in cutting relation through a work piece.

A portion of a machine of such general type is illustrated herein, and includes a vertically disposed column structure II], the upper portion only of which is shown. At the forward side of column I there is provided any suitable work holding means or table identified generally in Fig. 1 by the reference character W. A cutter head I4 is supported in position over and above work table W on the outer end of a supporting link structure identified generally by the reference character I5 (see U. S. Patent 2,000,838 referred to above) for universal lateral movements of the cutter head in a horizontal plane over the work table. The supporting link structure I5 is comprised of a link I5a which is pivotally mounted on and supported from a rigid, horizontally disposed arm structure IIla on and extending forwardly from the upper end of the column structure I0, and a link I5b pivotally coupled to the forward end of link I511. The cutter head I4 is mounted in vertically disposed position at the outer, free end of such link I 51). A rotary cutter spindle unit I6 is mounted in cutter head I4 and includes the rotary cutter spindle I6a journalled therein in vertically disposed position and movable as a unit therewith. Cutter spindle unit I6 is itself mounted in vertically disposed position in cutter head I5 for vertical sliding movements axially therein to raise and lower the unit with the cutter spindle I6a toward and from the work table W to thereby move a suitable cutting tool, such as a milling cutter C to and from cutting engagement with a work piece B on table W. This cutter spindle unit I6 is in this example spring loaded by a spring I6b which acts to continuously bias the cutter spindle Ifia in a direction to move the cutter spindle from cutting relation with a work piece B on the table W. The mounting and spring loading of the cutter spindle IBa in the cutter spindle unit I6 is in general accord with the established practice for mounting the cutter spindle in this type of machine, as exemplified for example in the U. S. patents referred to above, and in such U. S. Patents as Nos. 1,750,594-March 11, 1930, and 2,128,611August 30, 1938.

A pantograph linkage P is mounted in horizontally disposed position above the cutter head I4 and the cutter spindle unit I6 therein. Panto- 1 graph P is pivotally hung or suspended from a rigid supporting arm I0b which is mounted on rigid supporting structure Illa of the column I0. Pantograph P is comprised of the sets of parallel bars or links 2 and 4, and 3 and 6, respectively, and is pivotally mounted and suspended from arm IIlb by a pivotal connection I00 between the arm I01) and a slider block 4a which is mounted on and which slidably adjustably receives the pantograph link 4. The movement reducing bar or link 6 is pivotally coupled with the upper side of the link I5b of the cutter head supporting link structure I5 by a slider block 6a which is pivotally mounted on link I51) in position above but in 4 pivoted slider block 6a adjustably receives therein and mounts the link 6 of pantograph P.

Link 3 of pantograph P is extended longitudinally to provide the tracer arm T which mounts at its outer free end a stylus S for scanning or tracing engagement over a suitable pattern or master. It so happens that in the example ma chine a power driven master M is provided with which stylus S is connected and by which stylus S is caused to be moved around an endless profile path provided by the master unit. Our invention is not limited to the use of a power driven master unit as the stylus S on the tracer arm T may be manually operated to scan a pattern or master. In whatever manner stylus S is caused to trace a pattern, such tracing movements thereof will be transmitted to the pantograph linkage P by tracer arm T. Such movements of the tracer arm will in turn be transmitted by the pantograph through link 6 thereof and the slide block 6a, to the cutter head supporting link structure I5 and to the cutter spindle unit I 6 mounted in the link I5b as movements laterally of the spindle I6a in accurately reduced scale to the movements laterally of stylus S in following a pattern.

In the example machine the cutter spindle I6a mounts a spindle driving pulley I thereon at the lower end thereof and a suitable belt drive is provided which includes a belt I'I engaged over and in driving relation with the spindle pulley I60. It is not considered necessary to disclose herein in detail such belt drive beyond the illustrated portion of the belt I! as such a drive is old and well known and may be considered to be of the general types disclosed in the U. S. Patents Nos. 1,790,581January 27, 1931, and 1,925,036 August 29, 1933.

In accordance with out invention We provide ror automatically feeding the cutter spindle Ifia toward the work table W as the cutter spindle is universally laterally moved thereover by the pantograph linkage P to thereby feed a cutting tool C into a work piece B on table W as such cutting tool is moved laterally in cutting relation through the work piece. Following the teachings of our invention, such progressive feeding of the cutter spindle I6a may include periods in which the feed axially of the cutter C by the cutter spindle into the work piece is arrested but the period of feed and the period or periods of arrestation of feed, if any, are in the particular example hereof, preferably carried out and performed in a single automatic cycle.

The cutter spindle IE1: is continuously biased by the spring I 61) in a direction to move the spindle and a cutter C thereon away from a work piece B on table W. Cutter spindle I6a is only moved toward the work piece B by the application of forces to the spindle unit I6 of a magnitude to overcome the spring loading provided by the spring I 6b. In the example adaptation of the invention, the outer or upper end of spindle unit I6 is provided with an upstanding member such as the pin 39. This pin 39 is axially disposed relative to the unit I6 and to the depending cutter spindle IBa at the opposite end of the unit. Pin 39 provides by its upper end the point at which spindle feeding forces may be eiliciently applied to the spindle unit I6 to move that unit downwardly and inwardly through its mounting in the cutter head I4 in order to thereby move cutter spindle I6a and a cutter C mounted thereon into operative cutting engagement with a work piece axial alignment with cutter spindle IBa. The B mounted on table W,

messa e? The feeding: of thecutter: spindle Sui-and: its: cutter C'is, by our invention; carriedput auto.- matically by an organization which hastaken a form in the present example, in which aupow-er driven cam member 4|] is rotatedi with'thecam surface 4| thereof continuously engaged by'thc upper end of the pin 39 f Jspin'dle unit .I so that such pin functions as a cam follower under'the: action of the biasing spring ISbi'of spin'dle unit I63 Referring now to Figs. 2, 3, 4 and 5, the cam member 40' is in the form of. acircular disc having'ta peripheral flange 40a therearound at the .inner or under side thereof, with'theinner annular edge of this flange providing the annular cam surface 4| concentric with the'axis of rotation'of thecamu Byour invention; we mount'the cam member 40 on the link |5b ofthe supporting linkage I5 in' a position above cutter spindle unit IG'and the actuating pin 33:thereof so that the cam surface 4i will be continuously engaged by pin 39Jas the cam is rotatedfaboutan' axis parallel .withbut radially offset from the. vertical o'r'lon'gitudinal axis of cutterunit'lt and thecutter'spindle |6a therein mounted.

In'the specific example apparatus rhereof th'e link ldb of the cutter head supporting link struce ture I5 is provided with an over arm |5c which extends outwardly over and across and which'is spaced from the cutter head l4 and theouteror upper end of thecutterspindle unit It and its actuating pin or camfollower 39 (see Figs. 2 and 4). The feed. cam 40 is mounted from this over arm |5cbetween such arm and the cutter spindle unit it, on a stud shaft 42. This shaft szis mounted in fixed position on and extends inward 1y from theover arm I50 with its longitudinal axis parallel with but offset radially a distance in wardly from the longitudinal axis of the cutter spindle unit l6 and its actuatingpin 39. The feed cam 49 is journaled and confined on the inwardly extended length of shaft 42 bya suitable annular anti-friction bearing assembly 42a; The cam. and its bearing assembly l-lZa 'are' preferably removably mounted and confined in. position" on shaft 42 by a nut member 42b threaded onto the inner end of the shaft 42. relative positioning of the shaft 42. and'the feed cam 'itlthereon, is such that that portion of the cam profile or surface 4| above the pin 39 is aligned with that pin andengaged thereby in slidable, camming contact therewith. As'theicam surface i4is annular and is concentric withfthe axis of rotation of cam 46.! on its mounting'sh'aft at, it follows that as cam'4d is revolved, the annular cam surface 4| thereof will continuously pass through the plane of the axis of pin 39 for constant engagement of the cam surface 4| by such pin.

The feed cam 40 in this example is power driven from an electric motor FM which, in this instance, is mounted and supported from structure it in a location spaced a distance below the master unit M, as will be clear by reference to Fig. l. Preferably the motor FM is controllable selectively as to the rate of speed of'operation thereof throughthe medium of a rheostat 43 mounted on the column structure above motor FM. The rheostat 43 may be provided with an operating knob 43a in a position readily accessible to the operator. A speed reduction unit 114 is operatively connected with and driven from motor FM and provides a power output or take-off shaft 44a extending upwardly therefrom. Any suitable flexible shafting 45 is connected with the take-off shaft 44a and extends upwardly therefrom and The location and the 4 forwardly-across column structure l0 and-itsarm.

|0a:tostheiover :arm;:| 5a of: thecutter head supportingilink I51; :and" is 'coupled inr operative driving connection with the *feedcam 40.:

Th'efeeda'cam 40;.referring particularly to Figs.

3 "and:4- of .thedrawings, is provided with a'spiral gear or worm .wheelz lt fixed in position thereon the annular cam surface 4 I. ably mountedin a supporting structure 41a which is secured'and attached iniposition by means of a bracketistructure-4lb. attached to link- |5b -of. spindle'supportingstructure 5, w-iththe wormll l being-zpositioned-jtherebyitangentially relative to. and-in meshwithwormwheel 45 on the feed cam 40; The wormz4l iscoupled with and driven by the flexible shafting 45 fl'Ol'l'lfth8.m0tO1' FM vtov therebyrevolve'ztherfeed-camAEl; Thus, the feed cam 40 andits power driven transmissionwhich. includes the 'wormawheel 46 and worm 41,. are mountedrand supported on: the universal. laterally swingable cutter headisupporting linkage I5. By.

such arrangement :and mounting. the feed cam.

40i'with' the. worm 'wheel 4%, worm 4i and the flexible shaft connected therewith, aremovableswith' the linkage it as a unit. organization.

and: are rmaintaincd constantly in. operative en.- gagement throughout all movements laterally of the linkage: The flexible shafting45from motor.

Flvlitoworm' i'l freely-permits of such movements with a minimum of interference therewith.

The position of a feed cam'MLrelative-to the cutter spindleunit' lfi'is' such that the maximum outward or upward movement of cutter spindle unit 15 which is permittedrby. any pointon the. annular'cam surface 4| is less than themaxi mum; unrestrained outward movement possible to thatunit, so that, the biasing spring |6b of the' unit .will actto effectively maintain the pin 39 biasedwconstantly;into engagement with the cam surface;

The annular camsurface 4| isgeneratedto liei-in a generally helical on spiral path about the axis "of the cam and its :mounting shaft 42, from a" point 'or'sectorr on. cam surface 4| which when in engagement with'pin' EQ-permits the cutter unit lfiito move upwardly or outwardly-under its springi loading to therebyvmove the cutterC' on cutter spindle l6 fromcutting engagement-with a' work pieceBr, to apoint-or sector thereon at which the" cutter spindle is is forced inwardly to position cutter'C forits maximum, predetermined depth of .cut in the'work piece. Referring toJFig; 3, the=lowpointer sector on cam surface4|-at .which-the-cutter spindle unit it is in position with the cutter C mounted thereon removed from" operative engagement with. the work. piece is' indicated at a, while the high point: orsectoron cam surface' il at which the cuttertspi'ndle unit lfi-is-forced inwardly to.posi-. tion the cutter C at maximum depth of cut inthe work 'piece'; is indicated: at b. In thev particular form-"of the cam: 4d. of =this example,- the-points a and": b on cam-surface- 4| are joined" by a straight edge: portion 'cxof'cain flange Mia which is disposed in =a=planeisubstantially parallel with the axis of the cam. Hence, when pin 39 reaches point D on cam surface 4| movement of the cam 46 to the right or in an anti-clockwise direction will cause pin 39 with cutter spindle IE to abruptly move from point I) outwardly or upwardly under the action of spring |6b to engage pin 39 with the low point a of the cam surface and thus move cutter C from operative cutting engagement with a work piece B. From the "low point or sector a, cam surface 4| generally, progressively spirals through a relatively fiat spiral path around the cam to the high point or sector 1) thereof. Cam 40 is designed to provide the annular cam surface 4| thereof for a complete spindle feeding cycle of the cutter spindle from its starting position to its position of maximum depth of cut in a work piece in one (1) revolution of the cam.

The cam 48 of the instant example has the cam surface 4| thereof designed for controlling automatically in a single revolution of the cam, the feed of the cutter spindle during the cutting or milling out on a work piece B of an integral member having a continuous uninterrupted profile or contour therearound. In the example machine with which this cam 40 is employed, the powered master unit M provides an enlarged scale endless track which is a precise replica of the contour or profile of the integral member to be milled out from the work piece. In this particular form of cam 40, the cam surface 4| is formed so that the high sector 1) thereof provides a dwell of the required number of degrees around the cam surface to permit the cutter C to make one or more passes around the integral member which has been milled out from the work piece B. During such passes the inward feed of cutter C has been arrested and the cutter is maintained at the maximum depth of the cut required to form the integral member from the work piece. The sector of the cam surface 4| at such dwell is disposed in a plane perpendicular to the axes of the cam 49 and the cutter spindle unit pin 39, so that movement of this dwell sector I) of the cam surface that is in engagement with pin 39 will not result in any inward feeding movement of the cutter C. Similarly, a dwell of the required number of degrees for delaying initiation of the feed of cutter C at the start of a milling cycle may be provided through the required number of degrees through a sector on cam surface 4| beginning at the low point a thereof. Such a sector of cam surface 4| has the plane of the surface thereof perpendicular to the axes of the cam 49 and pin 39 of the cutter spindle unit l6. And in similar manner, if desired or found expedient in any particular design of cam 40 for performing a specific cutting operation, a dwell or dwells may be provided on the cam surface 4| at any location or locations intermediate the low point a and the high point 12.

Other departures from the normal progressive spiral path of cam surface 4|, at any desired point or points thereon, may be provided in order to control the feeding movements of the cutter spindle unit IE to meet any particular conditions which may be encountered in the cutting, milling or engraving of a work piece by the cutter 0.

Attention is directed to the fact that due to the removable mounting provided for the feed cam 40, such cam may be readily replaced by a cam of different characteristics for controlling the feed of the cutter spindle unit |6, so that,

a wide range of cams may be made available for for interchangeable mounting in the machine or combination of the invention in order that the combination may be operated to cut out, mill or engrave over a wide variety of operations, designs, profiles and contours.

It will also be evident that various other embodiments, modifications, changes, substitutions, eliminations, additions and variations may be resorted to without departing from the basic spirit and scope of our invention, and hence we do not intend or desire to limit our invention to the embodiment and application thereof herein disclosed, or to the exact and specific constructions and arrangements thereof, except as may be required by any intended limitations thereto in any of the appended claims.

What we claim is:

1. In combination; a cutter spindle supporting structure mounted for lateral swinging over a work piece; said supporting structure including a. link member pivotally mounted at its inner end and provided at its outer end with spaced, substantially parallel arms; a cutter spindle unit mounted in and disposed transversely through one of said arms with one end of said spindle unit positioned intermediate said arms in the space therebetween and with the opposite, outer end thereof adapted to mount a cutting tool; said cutter spindle unit being also mounted for movements axially toward and from a work piece; a. feed cam mounted in position at the inner side of the other of said arms for rotation about an axis parallel with the axis of said spindle unit; said feed cam being provided with an annular cam surface therearound in camming engagement with the end of said spindle unit positioned between said arms for progressively feeding said spindle unit toward a Work piece during lateral movements of said unit with said supporting structure; feed cam rotating mechanism mounted on and movable as a unit with said link member in driving connection with said feed cam; and a motor in driving connection with said cam rotating mechanism for effecting power feed of said cutter spindle unit.

2. In the combination defined by claim 1, said feed cam rotating mechanism comprising, a worm wheel mounted on said feed cam concentric with said annular cam surface, a worm supported and journaled on that arm of said spaced arms on which said feed cam is mounted in driving mesh with said worm wheel, and a drive shaft connecting said motor with said worm.

ROBERT J. STUART. ALLEN D. GUNDERSON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,899,775 Schnable Feb. 28, 1933 2,341,061 Rhodes et al Feb. 8, 1944 FOREIGN PATENTS Number Country Date 558,215 Great Britain Dec. 24, 1943 

